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Unless you’ve been living under a case of 1 farad capacitors, you’ve heard of the Amazon Echo. Roughly the size of two cans of beans, the Echo packs quite a punch for such a small package. It’s powered by a Texas Instrument DM3725 processor riding on 256 megs of RAM and 4 gigs of SanDisk iNAND ultra flash memory. Qualcomm Atheros takes care of the WiFi and Bluetooth, and various TI chips take care of the audio codecs and amplifiers.

What’s unique about Echo is its amazing voice recognition. While the “brains” of the Echo exist somewhere on the Internets, the hardware for this circuitry is straight forward. Seven, yes seven microphones are positioned around the top of the device. They feed into four Texas Instrument 92dB SNR low-power stereo ADCs. The hardware and software make for a very capable voice recognition that works from anywhere in the room. For the output sound, two speakers are utilized – a woofer and a tweeter. They’re both powered via a TI 15 watts class D amplifier. Check out this full tear down for more details of the hardware.

Now that we have a good idea of the hardware, we have to accept the bad news that this is a closed source device. While we’ve seen other hacks where people poll the to-do list through the unofficial API, it still leaves a lot to be desired. For instance, the wake word, or the word which signals the Echo to start listening to commands, is either “Alexa” or “Amazon”. There is no other way to change this, even though it should be easily doable in the software. It should be obvious that people will want to call it “Computer” or “Jarvis”. But do not fret my hacker friends, for I have good news!

It appears that Amazon sees (or had seen all along) that home automation is the future of the Echo. They now officially support Philips Hue and Belkin WeMo gadgets. The Belkin WeMo, which is no stranger to the hacker’s workbench, has a good handle on home automation already, making the ability to control things in your house with the Echo tantalizingly close. See the video below where I test it out. Now, if you’re not excited yet, you haven’t heard of the WeMo Maker, a device which they claim will let you “Control nearly any low-voltage electronics device“. While the WeMo Maker is not supported as of yet, it surely will be in the near future.

We know it sucks that all of this is closed source. But it sure is cool! So here’s the question: Is the Echo the future of home automation? Sure, it has its obvious flaws, and one would think home automation is not exactly Amazon’s most direct business model (they just want you to buy stuff). However, it works very well as a home automation core. Possibility better than anything out there right now – both closed and open source.

Do you think Amazon would ever open the door to letting the Echo run open source modules which allow the community to add control of just about any wireless devices? Do you think that doing so would crown Amazon the king of home automation in the years to come?

Your mission, should you choose to accept it, is to send a quadcopter to near space and return it safely to the Earth. Getting it there is not that difficult. In fact, you can get pretty much anything you want to near space with a high altitude weather balloon. Getting it back on the ground in one piece is a whole other ballgame.

Why does someone need to do this? Well, it appears the ESA’s StarTiger team is taking a card out of NASA’s book and wants to use a Sky Crane to soft land a rover on Mars. But instead of using rockets to hold the crane steady in the Martian sky, they want to use…you guessed it, a quadcopter. They’re calling it the Dropter.

At first glance, there seems to be a lot wrong with this approach. The atmosphere on Mars is about 100 times less dense than the Earth’s atmosphere at sea level. How do props operate in these conditions? Testing would need to be done of course, and the Earth’s upper atmosphere is the perfect place to carry out such testing. At 100,000 feet, the density of the stratosphere is about the same as that of the Martian surface atmosphere. AND 100,000 feet is prime high altitude balloon territory. Not to mention the gravity on Mars is about 38% of Earth’s gravity, meaning a 5.5 pound model on Earth could accurately represent a 15 pound model on Mars.

With all of these facts taken into consideration, one can conclude that realistic testing of a scale model Martian quadcopter is within the grasp of the hacker community. We’ve seen some work on high altitude drones before, but never a quadcopter.

Now it’s your turn to do something no one has ever done before. Think you got what it takes to pull such a project off? Let us know what your approach to the challenge would be in the comments.

It’s no secret the Hackaday tip line gets a lot of email from Kickstarter campaigns and PR firms managing Kickstarter campaigns. Most of these are terrible products. Want a five-pound battery that can’t be recharged? Yeah, stuff like that.

Every once in a while, we come across a tip that’s a completely original idea. There’s a balance between ingenuity and practicality with these ideas, and I can’t figure out where this one sits. It’s a Kickstarter for perfboard, yes, but not like any perfboard you’ve ever seen.

Busboard, or solderable breadboard

Before we dig into this, let’s get some definitions straight. Perfboard is a sheet with holes drilled on a 0.1″ grid. The holes are plated on both sides, and each hole is an individual electrical node. Veroboard, or stripboard is a bunch of holes on a 0.1″ grid. These holes are also plated, but all the holes in a column are a single electrical node. You can cut the tracks between holes, but the basic idea here is to reduce the number of wires needed to connect components. Busboard, seen left, is a continuation of Veroboard, and is laid out like a solderless breadboard.

And so we come to the new invention, Perf+, the perfboard reinvented. This perfboard again is a series of plated holes on a 0.1″ grid. Alongside these holes is a plated bus. This bus does not connect to any hole; instead, a little bit of solder is used to connect it to holes on the same row or column. “Selective Veroboard,” you could call it.

Now for the real trick: on one side of the board, the plated busses run vertically. On the other side of the board, the plated busses run horizontally. This means any two holes on the protoboard can be connected as one electrical node simply with a bit of solder.

If ever there was an idea you could point to and simultaneously say, “that’s clever” and “I have no idea how to use this,” there you go. I’m pretty sure this idea isn’t better than a piece of stripboard, but it is different. If you have any idea of how to used this new, strange, and otherworldly protoboard for something useful, put a note in the comments.

When most think of a microwave, they think of that little magic box that you can heat food in really fast. An entire industry of frozen foods has sprung up from the invention of the household microwave oven, and it would be difficult to find a household without one. You might be surprised that microwave ovens, or reactors to be more accurate, can also be found in chemistry labs and industrial complexes throughout the world. They are used in organic synthesis – many equipped with devices to monitor the pressure and temperature while heating. Most people probably don’t know that most food production facilities use microwave-based moisture solids analyzers. And there’s even an industry that uses microwaves with acids to dissolve or digest samples quickly. In this article, we’re going to look beyond the typical magnetron / HV power supply / electronics and instead focus on some other peculiarities of microwave reactors than you might not know.

Single vs Multimode

The typical microwave oven in the millions of households across the world is known as multimode type. In these, the microwaves will take on typical wavelike behavior like we learned about in physics 101. They will develop constructive and destructive interference patterns, causing ‘hot spots’ in the cavity. A reader tipped us off to this example, where [Lenore] uses a popular Indian snack food to observe radiation distribution in a multimode microwave cavity. Because of this, you need some type of turntable to move the food around the cavity to help even out the cooking. You can avoid the use of a turn table with what is known as a mode stirrer. This is basically a metal ‘fan’ that helps to spread the microwaves throughout the cavity. They can often be found in industrial microwaves. Next time you’re in the 7-11, take a look in the top of the cavity, and you will likely see one.

Multimode microwaves also require an isolator to protect the magnetron from reflected energy. These work like a diode, and do not let any microwaves bounce back and hit the magnetron. It absorbs the reflected energy and turns it into heat. It’s important to note that all microwave energy must be absorbed in a multimode cavity. What is not absorbed by the food will be absorbed by the isolator. Eventually, all isolators will fail from the heat stress. Think about that next time you’re nuking a small amount of food with a thousand watts!

Single Mode microwaves are what you will find in chemistry and research labs. In these, the cavity is tuned to the frequency of the magnetron – 2.45GHz. This allows for a uniform microwave field. There is no interference, and therefore no hot or cold spots. The microwave field is completely homogenous. Because of this, there is no reflected energy, and no need for an isolator. These traits allow single mode microwaves to be much smaller than multimode, and usually of a much lower power as there is a 100% transfer of energy into the sample. While most multimode microwaves are 1000+ watts, the typical single mode will be around 300 watts.

Power Measurement

Most microwave ovens only produce one power level. Power is measured and delivered by the amount of time the magnetron stays on. So if you were running something at 50% power for 1 minute, the magnetron would be on for a total of 30 seconds. You can measure the output power of any microwave by heating 1 liter of water at 100% power for 2 minutes. Multiply the difference in temperature by 35, and that is your power in watts.

There are other types of microwaves that control power by adjusting the current through the magnetron. This type of control is often utilized by moisture solids analyzers, where are more precise control is needed to keep samples from burning.

Have you used a microwave and an arduino for something other than cooking food? Let us know in the comments!

It wasn’t long ago that we saw the Echo bloom into existence as a standalone product from its conceptual roots as a smartphone utility. These little black columns have hardly collected their first film of dust on our coffee tables and we’re already seeing similar technology debut on the toy market, which causes me to raise an eye-brow.

There seems to be some appeal towards making toys smarter, with the intent being that they may help a child learn while they play. Fair enough. It was recently announced that a WiFi enabled, “Hello Barbie” doll will be released sometime this Fall. This new doll will not only be capable of responding to a child’s statements and questions by accessing the Internet at large, it will also log the likes and dislikes of its new BFF on a cloud database so that it can reference the information for later conversations. Neat, right? Because it’s totally safe to trust the Internet with information innocently surrendered by your child.

Similarly there is a Kickstarter going on right now for a re-skinned box-o-internet for kids in the shape of a dinosaur. The “GreenDino”, is the first in a new line called, CogniToys, from a company touted by IBM which has its supercomputer, Watson, working as a backbone to answer all of the questions a child might ask. In addition to acting as an informational steward, the GreenDino will also toss out questions, and upon receiving a correct answer, respond with praise.

Advancements in technology are stellar. Though I can see where a child version of myself would love having an infinitely smart robot dinosaur to bombard with questions, in the case of WiFi and cloud connectivity, the novelty doesn’t outweigh the potential hazards the technology is vulnerable to. Like what, you ask?

Whether on Facebook or some other platform, adults accept the unknown risks involved when we put personal information out on the Internet. Say for instance I allow some mega-corporation to store on their cloud that my favorite color is yellow. By doing so, I accept the potential outcome that I will be thrown into a demographic and advertised to… or in ten years be dragged to an internment camp by a corrupt yellow-hating government who subpoenaed information about me from the corporation I consensually surrendered it to.

The fact is that I understand those types of risks… no matter how extreme and silly they might seem. The child playing with the Barbie does not.

All worst case scenarios of personal data leakage and misuse aside, what happens when Barbie starts wanting accessories? Or says to their new BFF something like, “Wouldn’t we have so much more fun if I had a hot pink convertible?”

It’s amazing how affordable PCB fabrication has become. It has long been economical (although not always simple) to fabricate your own singe and double-sided boards at home, the access to professional fabrication is becoming universal. The drive continues downward for both cost and turnaround time. But there is growing interest in the non-traditional.

Over the last year we’ve seen a huge push for conductive-ink-based PCB techniques. These target small-run prototyping and utilize metals (usually silver) suspended in fluid (think glue) to draw traces rather than etching the traces out of a single thin layer of copper. Our question: do you think conductive in will become a viable prototyping option?

Voltera V-One Circuit Board Prototyping Machine

I recorded this interview at 2015 CES but was asked not to publish it until their crowd funding campaign went live. If you haven’t been paying attention, Voltera is at almost 400% of their $70k goal with 26 days remaining. This printer definitely works. You can print circuits, solder components or reflow them, and there’s even a second non-conductive ink that can be used to insulate between traces when they cross over one another. In the video [Alroy] suggests Voltera for small production runs of 10-20 boards. Would you see yourself using this for 10-20 boards?

Personally, I think I could solder point-to-point prototypes in less time. Consider this: the V-One will print your traces but you still must solder on the components yourself. If the board design reaches a high level of complexity, that timing may change, but how does the increased resistance of the ink compared to copper traces affect the viability of a board? I assume that something too complex to solder point-to-point would be delving into high-frequency communications (think parallel bus for LCD displays, etc.). Is my assumption correct? Do you think conductive ink will get to the point that this is both viable and desirable over etching your own prototypes and how long before we get there?

Now, I certainly do see some perfect use-cases for Voltera. For instance, introduction to circuit design classes. If you had one of these printers at the middle school or high school level it would jump-start interest in electronics engineering. Without the need for keeping chemical baths like Cuperic Chloride or Ferric Chloride on hand, you could walk students through simple board design and population, with the final product to take home with them. That’s a vision I can definitely get behind and one that I think will unlock the next generation of hardware hackers.

Correction: [Arachnidster] pointed out in the comments that Voltera is still working on being able to reflow boards printed by the V-One. On their Kickstarter page they mention: “(Reflow onto Voltera printed boards is currently under development)”

While many of us have made and documented our open source projects, not many of us have tried to sell our design to the masses. [Scott] developed, marketed, and “bootstrapped” a cool looking MIDI controller. Now, before you get your jumpers in a bunch – the project is completely open source. [Scott] documented the entire process of not only the design, but the trials and tribulations of bringing it to market as well. Calculating costs, FCC testing and the many other challenges of bringing a consumer electronics device to market are all detailed in his blog. Join me while we look at the highs and lows of his interesting and eventually worthwhile journey.

Putting yourself into a game where orders are in the tens of thousands, with hundreds of thousands of dollars changing hands is not easy when you’re just a guy with an idea and a soldering iron. [Scott] was up for the challenge, however. He quickly realized that much of the margin is spent on advertising and to cover risk. On his last order, some of the paint was chipping off. He had to fix the paint and repackage everything – all at his cost.

He also talks about the learning process of product design along the way. His original idea was to make a volume controller, but couldn’t sell a single one. He was forced to redesign the software into the MIDI controller as it exists today. He tried to launch a Kickstarter, but was rejected. This turned out to be a good thing, however, because he would have wound up kickstarting a product that didn’t work.

For advertising, he relied on Google and made some extremely detailed tutorials for his product. Many of them can be used for other MIDI controllers, and often come up in Google searches. Smart. Very smart.

Be sure to check out the video below, where [Scott] gets into some capacitive touch design theory, and talks about how not to cut your final product in half while on the CNC.

Have any of you ever tried to mass produce and sell one of your designs? Let us know in the comments!